IB Bio Human Body all parts

concentration gradient

A difference in the concentration of a substance across a space.

exchange surface

A surface where materials are exchanged between an organism and its environment.

ventilation

The process of moving air in and out of the lungs.

bronchioles

The small air passages in the lungs that branch from the bronchi.

capillary

A tiny blood vessel where gas and nutrient exchange occurs.

surface area

The total area of the surface of an object, important for exchange processes.

alveoli

Small air sacs in the lungs where gas exchange takes place.

surfactant

A substance that reduces surface tension in the alveoli, preventing collapse.

diaphragm

The primary muscle used in the process of breathing.

intercostal muscles

The muscles located between the ribs that assist in breathing.

abdominal muscles

Muscles that aid in respiration and support the abdominal cavity.

ribs

The bones that form the rib cage, protecting the thoracic cavity.

tidal volume

The amount of air inhaled or exhaled in a normal breath.

vital capacity

The maximum amount of air a person can expel from the lungs after a maximum inhalation.

inspiratory reserve volume

The additional air that can be inhaled after a normal inhalation.

expiratory reserve volume

The additional air that can be exhaled after a normal exhalation.

fenestrations

Small openings in capillaries that allow rapid exchange of materials.

arteries

Blood vessels that carry blood away from the heart.

veins

Blood vessels that carry blood toward the heart.

lumen

The inside space of a tubular structure, such as a blood vessel.

elastic tissue

Tissue that can stretch and recoil, important in arteries.

muscle layer

A layer of muscle in blood vessels that regulates blood flow.

valves

Structures in veins that prevent backflow of blood.

pulse rate

The number of heartbeats per minute.

heart rate

The number of times the heart beats in one minute.

coronary arteries

The arteries that supply blood to the heart muscle.

occlusion

The blockage of a blood vessel, impeding blood flow.

coronary heart disease

A condition characterized by reduced blood flow to the heart.

correlation coefficient

A statistical measure that indicates the extent to which two variables fluctuate together.

cell respiration

The process by which cells convert glucose and oxygen into energy.

ATP

Adenosine triphosphate, the energy currency of the cell.

aerobic respiration

Cellular respiration that requires oxygen.

anaerobic respiration

Cellular respiration that occurs without oxygen.

respiratory substrates

Substances used by cells to create energy during respiration.

glucose

A simple sugar that is an important energy source.

fatty acids

The building blocks of lipids, used in energy production.

mitochondria

Organelles that are the site of aerobic respiration in cells.

rate of respiration

The speed at which respiration occurs in an organism.

photosynthesis

The process by which green plants and some other organisms use sunlight to synthesize foods with the help of chlorophyll.

chlorophyll

A green pigment found in plants that is essential for photosynthesis.

cell membrane

A protective barrier that controls what enters and exits a cell.

nucleus

The central part of a cell that contains genetic material.

ribosome

A small organelle where proteins are synthesized.

cytoplasm

The gel-like substance within the cell membrane, excluding the nucleus.

ATP synthase

An enzyme that synthesizes ATP during cellular respiration.

fermentation

A metabolic process that converts sugar to acids, gases, or alcohol without oxygen.

glycolysis

The breakdown of glucose to extract energy for cellular metabolism.

oxygen

A gas that is essential for aerobic respiration.

carbon dioxide

A byproduct of cellular respiration that is released into the atmosphere.

enzyme

A protein that acts as a catalyst to speed up chemical reactions in the body.

gene

A segment of DNA that contains coding for a protein or RNA.

chromosome

A tightly coiled structure made of DNA and proteins that contains genetic information.

mutation

A change in the DNA sequence that can lead to variations in traits.